1. Field of the Invention
The present invention relates to an electrical heating device, in particular to an electrical heating device as auxiliary heater for a motor vehicle and is based on an electrical heating device comprising a housing, which forms oppositely situated air passage areas on each of which at least one air passage aperture is formed. The housing incorporates a heating block. This heating block comprises at least one PTC heating element and at least one radiator element which abuts it.
2. Description of the Related Art
A generic electrical heating device is for example known from EP 0 350 528. With this state of the art the PTC heating elements consist of one, preferably a plurality of PTC elements in one level on the oppositely situated sides of which sheet metal bands abut, of which some are extended sidewards beyond the heating block to form electrical connecting elements. These electrical connecting elements are normally exposed on the outer side of the housing. Meander-type, curved sheet metal strips are frequently used as radiator elements.
Electrical heating devices of this nature nowadays are normally used in air conditioning devices. These air conditioning devices have an air conditioning housing enclosing a heat exchanger, which can be connected to a cooling water circuit of a motor vehicle. The air conditioning housing also accommodates the motor-vehicle auxiliary heater to heat air normally flowing through the air conditioning housing when the internal combustion engine is relatively cold. In this respect the air conditioning housing has an insertion opening for the motor-vehicle additional heating device on the outer side of the air conditioning housing. Situated opposite to this insertion opening is a boundary wall formed by the air conditioning housing and which normally forms mounting apertures which accommodate mounting pins which are provided protruding beyond this outer surface on that outer surface of the housing of the motor-vehicle auxiliary heating which is adjacent to the boundary wall when the motor-vehicle heating device is installed.
An air conditioning housing is described generally in DE 33 31 890 C2. An appropriate housing with motor-vehicle additional heating is disclosed in the article “Integrales Klimasystem für Elektroautomobile” [Integral air conditioning system for electric cars], ATZ—Automobiltechnische Zeitschrift, November 1992 by Burk, Krauss, Dr. Löhle.